<!DOCTYPE html >
<html id="ahhcGKZR68aXOsALvsGg_tplLgoq-7689721" data-origid="7689721" class="anndoc" data-anndoc-version="2.0" lang="" xml:lang="" xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta charset="UTF-8"/>
    <meta name="generator" content="net.tagtog.anndoc.v2.parsers.bio.PubMedAbstractsParser_v0_1$"/>
    <meta name="dcterms.source" content="http://www.ncbi.nlm.nih.gov/pubmed/7689721"/>
    <title>ahhcGKZR68aXOsALvsGg_tplLgoq-7689721</title>
  </head>
  <body>
    <article>
      <section data-type="title">
        <h2 id="s1h1">Identification and characterization of multiple mdm-2 proteins and mdm-2-p53 protein complexes.</h2>
      </section>
      <section data-type="abstract">
        <h2 id="s2h1">Abstract</h2>
        <div class="content">
          <p id="s2p1">A protein product of the mdm-2 oncogene (p90) has been recently shown to associate with the protein encoded by the tumor-suppressor gene p53. The mdm-2 gene was originally identified as a gene amplified in a spontaneously transformed Balb/c 3T3 cell line (3T3DM). This report describes the characterization of mdm-2 gene products and their interactions with the p53 protein. Polyclonal and monoclonal antibodies were generated against murine and human mdm-2 protein. These antibodies detected the mdm-2 p90 protein and at least four additional polypeptides (p85, p76, p74, p58-p57) in cultured cells. These additional proteins may arise from different spliced mRNA forms of the mdm-2 gene or post-translational modifications of the mdm-2 protein. The monoclonal antibodies distinguished at least three sets of mdm-2 proteins with distinct combinations of epitopes (p90 and p85; p76 and p74; p58-57). One or two of these proteins forms a complex with the p53 protein (p90, p58). These mdm-2 proteins were found to be overexpressed in 3T3DM cells and a subset of these proteins were complexed with p53. In 3T3DM cells, p90, like p53, had a short half-life of approximately 20 min and was localized to the cell nucleus. In resting cells stimulated with serum p90 levels and p90/p53 complex levels increased in the late G1 phase of the cell cycle. The p90 mdm-2 protein could regulate p53 activity in the late G1 phase of the cell cycle.</p>
        </div>
      </section>
    </article>
  </body>
</html>
